EPDM is a terpolymer whose rheological and physical and mechanical properties (eg, flow form and crystallinity) depend on the polymer composition (ie, the comonomer contained therein). The relative number). Due to the saturated main chain, EPDM has excellent electrical insulation properties. It can be used as insulation material for medium voltage and high voltage wires and cables.
In the past, people used polyvinyl chloride as insulation material. However, EPDM shows more prominent advantages than polyvinyl chloride. In particular, it has low sensitivity to ultraviolet radiation, low toxicity and corrosion, and chemical resistance. However, EPDM is highly flammable and requires the use of a large amount of flame retardant to protect it.
In general, the amount of flame retardant should be as high as 100 parts in order to give EPDM good flame retardancy. Therefore, compared with other rubbers, EPDM is relatively expensive, but it can accept a large number of fillers, ultimately reducing the cost of the product. EPDM has such comprehensive properties as good processability, low cost, light weight, and excellent insulation properties, which makes it widely used in the electrical field. In order to prevent the current-carrying conductive element from coming in contact with other elements and provide the conductor with suitable mechanical support, the insulating material may be thinly coated on the conductor.
Thermal overload in conductors (caused by defective joints) is a potential source of sparks that can cause entire electrical installations to be in danger. Because the polymer in the cable jacket is a highly flammable material. Therefore, in the field of electrical applications, special preventive measures need to be taken for the possibility of ignition of polymer materials.
